ISSN 0973-1555(Print) ISSN 2348-7372(Online) HALTERES,Volume 7, 112-119, 2016 DAVID EMMANUEL M. GENERAL doi: 10.5281/zenodo.55319 Romblonella longinoi (Hymenoptera: Formicidae), a new species and first record of the genus from Sabah, Malaysia, with a key to the species of Romblonella Wheeler, 1935 David Emmanuel M. General *University Researcher, University of the Philippines Los Baños Museum of Natural History, College, Los Baños, Laguna 4031, Philippines, and Research Associate, National Museum of the Philippines, Taft Ave, Ermita, Metro Manila 1000, Philippines. E-mail: [email protected] Abstract A new species of Romblonella Wheeler, 1935 from Sabah represents the first record of the genus for Malaysia. The worker and the associated male alate of Romblonella longinoi sp. n. are described. This new species is easily distinguished from all known species by its posteriorly broadened head capsule and coloration. An identification key to the workers of Romblonella is provided. Keywords: Romblonella, Formicidae, Sabah, new species, identification key Received: 31 March 2016; Revised: 31 May 2016; Online: 10 June 2016. Introduction MC120HD digital camera attached to the Leica Romblonella Wheeler, 1935 is a small S8 stereomicroscope. These images were genus of myrmicine ants, with nine known stacked using Combine ZM. The stacked species distributed from the Philippines to images were edited with Adobe Photoshop CS5. islands of the South Pacific, New Guinea, and Images of the external genitalia were created at Australia (Bolton, 2015; General and the MCZC Ant Room with Leica DFC 450 Buenavente 2015, Shattuck et al., 2014; Taylor, digital camera attached to a Leica M205C 1991). stereomicroscope. These source images were During the peer-review process of my stacked with Helicon Focus 5.3 64X. Stacked previous paper describing Romblonella coryae images were edited with Adobe Photoshop CS5 General and Buenavente, 2015 from the island Extended. of Palawan, Philippines, I was asked about a nest series collection from Sabah. The Sabah Measurements (in millimetres) material turned out to be a distinctive new EL Maximum diameter of compound eye. species, which I now describe in this present EW Maximum width of compound eye. contribution. GL Maximum length of gaster, from base of first gastral tergite to apex of gaster, Materials and Methods measured in lateral view. Specimens were examined and HL Maximum head length in full face view, measured with a Leica S8 stereomicroscope with measured from anterior-most point of ocular micrometer at PNM. Type specimens of clypeal margin to posterior-most point other species were examined and measured with of head capsule. a Wild 5A stereomicroscope with ocular AHW Anterior head width, maximum width in micrometer at MCZC. Images of the wings, front of the compound eyes, in full face head, and antennae were created using a Leica view. 112 Romblonella longinoi, a new species and first record of the genus from Sabah, Malaysia PHW Posterior head width, maximum width DMGC Private Collection, David behind the compound eyes, in full face Emmanuel M. General. view. JTLC Private Collection, John T. Longino. ML Mesosomal length measured from MCZC Museum of Comparative Zoology, anterior edge of the pronotum Harvard University, Cambridge, (excluding the collar) to posterior edge MA, USA. of propodeal lobe. PNM National Museum of the Philippines, PW Maximum width of pronotum in dorsal Manila, Philippines view. USNM United States National Museum of SL Length of scape, excluding basal neck Natural History, Washington, D.C., and condyle. USA. SPL Propodeal spine length, maximum distance from inner posterior margin of Synonymic list of species propodeal spiracle to propodeal spine coryae General, 2015 [holotype examined] apex. elysii (Mann, 1919) [cotype examined] PetL Petiole length, straight line length, in heatwolei Taylor, 1991 [not seen] lateral view, from anterior margin of liogaster (Santschi, 1928) [not seen] petiolar denticle to posterior inflection. = vitiensis M.R. Smith, 1953 PetW Maximum width of petiole in dorsal (synonymy by Sarnat and Economo view. 2012: 121) [not seen] PetH Petiolar height in lateral view, measured opaca (F. Smith, 1861) as the perpendicular distance from the = grandinodis Wheeler, 1935 ventral margin to the highest point of (synonymy by Bolton 1976: 294) posterolateral tubercles. [syntype examined] PPL Postpetiole length, straight line length, palauensis M.R. Smith, 1953 [paratype in lateral view, from anterior to posterior examined] inflections. scrobifera (Emery, 1897) [not seen] PPW Maximum width of postpetiole in dorsal townesi M.R. Smith, 1953 [paratype examined] view. yapensis M.R. Smith, 1953 [paratype examined] PPH Measured from sternal process base to postpetiole apex in lateral view. Taxonomy TL The total outstretched length of ant from Romblonella Wheeler, 1935 mandibular apex to gastral apex; when measured in profile the sum of Type species: Romblonella grandinodis mandibular length + head length + Wheeler, 1935 (junior synonym of Myrmica mesosomal length + lengths of waist opaca F. Smith, 1861), by original designation. segments + length of gaster. Romblonella longinoi General sp. n. Indices CI Cephalic index: PHW/HL x 100. urn:lsid:zoobank.org:act:78EC95E1-4BFE- EI Eye Index: EL/PHW x 100. 49B9-BC70-AD3913770D4E SI Scape index: SL/PHW x 100. Measurements and indices Collection Abbreviations (Brandão, 2000) Worker measurements of holotype ANIC Australian National Insect worker [paratype (n=17) mean: range in Collection, Canberra, Australia. brackets]: TL 4.01 [3.97: 3.67-4.14], HL 0.90 BMNH Natural History Museum, London, [0.89: 0.79-0.97], AHW 0.63 [0.69: 0.61-0.77], UK. PHW 0.85 [0.84: 0.77-0.90], SL 0.54 [0.50: CASC California Academy of Sciences, 0.36-0.58], EL 0.13 [0.18: 0.12-0.22], EW 0.13 San Francisco, CA, USA. [0.13: 0.11-0.14], PW 0.67 [0.63: 0.58-0.67], ML 1.13 [1.07: 1.01-1.13], SPL 0.43 [0.38: 113 David Emmanuel M. General 0.32-0.43], PetL 0.47 [0.42: 0.38-0.47], PetW erect hairs sparsely distributed over rest of body. 0.36 [0.35: 0.31-0.49], PetH 0.47 [0.43: 0.38- Body distinctly bi-colored; body yellow to 0.49], PPL 0.31 [0.30: 0.27-0.34], PPW 0.45 orange except for brown antennal club, legs, [0.45: 0.41-0.47], PPH 0.41 [0.39: 0.36-0.41], distal and lateral edges of first gastral segment, GL 1.08 [1.17: 1.03-1.42]. and gastral segments 2-5. Indices: CI 82 [86: 80-98], EI 16 [22: 13-25], SI 73 [65: 47-77]. Mean measurements (range in brackets) and indices of male paratype (n=2): TL 4.0 [3.96- Description of worker (Figures 1-4): 4.03], HL 0.72 [0.68-0.76], AHW 0.40 [0.40- In full face view, posterior margin of 0.40], PHW 0.69 [0.68-0.70], SL 0.15 [0.14- head shallowly emarginate; head longer than 0.16] , EL 0.38 [0.37-0.40], EW 0.28 [0.28- wide; sides of head diverging posteriorly; eyes 0.29], PW 0.57 [0.56-0.58], ML 1.14 [1.13- laterally located, slightly behind midlength of 1.15], GL 1.30 [1.30-1.30], CI 96 [93-100], EI head; shallow scrobe present; frontal carina 55 [53-58], SI 73 [70-76]. long, almost reaching the posterior margin of head; scapes short, exceeding posterior edge of Diagnosis of male paratype (Figures 5-15): eye by about 2X width of distal scape; antennal Alate; approximately as long as worker, formula 12:3; mandibles triangular, with 6 but more gracile. robust teeth; palp formula 5:3; median clypeus In full-face view, head longer than carinate, with a median carina flanked by 3 pairs broad; sides of head diverging posteriorly, of lateral carinae; median clypeus inserted posterior head width behind compound eyes between frontal lobes and about as wide as about ¾ wider than anterior head width; ocelli frontal lobe; anterior clypeal margin entire, not unusually large (compared with images of without an isolated median seta; head rugo- male R. palauensis, M.R.Smith, 1953), width of reticulate with short cross-hatches that reach the ocelli subequal to distance between lateral adjacent rugae; punctae in interstitial spaces; ocellus and median ocellus; lateral ocelli mandibles striate. separated by about 2X width of median ocellus; In lateral view, dorsal margin of compound eye large, convex, occupying about mesosoma evenly convex and arched, without 2/3 side of the head; posterior margin of head grooves or sutures; propodeal spines long and medially straight, laterally with lobes; antenna stout; petiole sessile, with anterodorsally long, subfiliform, with 13 segments (Figures 6 directed angle over petiolar spiracle; petiole and 7); length of antennomeres (one male massive, larger and taller than postpetiole; measured) antennal scape, 0.08 mm; anterior subpetiolar denticle present; spurs antennomere 2, 0.04 mm; antennomere 3, 0.27 absent on meso- and metatibia. mm; antennomere 4-7, range = 0.12-0.19 mm; In dorsal view, pronotum with angulate antennomere 8, 0.23 mm; antennomere 9-13, humeri; sides of promesonotum converging range = 0.13-0.18 mm; antennomere 4-7 slightly posteriorly; sides of propodeum subparallel but and gently broadened distally, such that the basal bulging slightly anterior to propodeal spiracle; end of succeeding segment is narrower than the stout propodeal spines slightly divergent through distal end; antennomere 3-7 broader than their entire length; mesosoma, petiole and antennomere 8-13; clypeus broadly projecting postpetiole dorsally reticulate with interstitial anteriorly, forming a rounded obtuse angle; punctulae; first gastral segment(= 4th abdominal) mandible triangular, well-developed and punctulate. functional; masticatory margin with 6 sharp Head with evenly distributed short, blunt triangular teeth; apical tooth longest, about 2X erect hairs that are shorter than distance between longer than preapical tooth; tooth 4 smallest; rest them; scape with suberect hairs; short, blunt of teeth subequal; palp formula 5:3.